本研究以 SACCHACHITIN （靈芝多醣幾丁質）進行研究，探討其對 酪胺酸 ? 活性的影響。由於之前已證實此材料能有效抑制蛋白質水解 酵素（如 MMP-1 ， MMP-8 ， MMP-9 ）以及脂肪 ? （ Lipase ），所 以本實驗將進一步探討其抑制酪胺酸 ? 活性之成效。本研究首先探討 對抑制蕈酪胺酸 ? （ Mushroom tyrosinase ）活性的影響性，結果顯示： 2.5 mg/ml 的抗壞血酸顯示出非常顯著的抑制作用，在不同來源的幾 丁聚醣中，只有 SACCHACHITIN 呈現劑量依存反應（ dose-dependent reaction ）其 IC50 約為 17.2 mg/ml 。接著在細胞模式下， SACCHAC HITIN 對 B16 細胞型態和增生沒有不良影響，不具有細胞毒性。再進 行 B16 細胞黑色素含量的分析，加入誘導劑 α-MSH 濃度為 25 nM 所 增加的百分比率最高，可以提高 3.37 倍的黑色素含量。不論在無或有 誘導劑之下， SACCHACHITIN 均可以減少 B16 細胞產生黑色素，和 降低 B16 細胞之酪胺酸 ? 活性，呈現劑量依存反應（ dose-dependent re action ）。西方點墨法再次確認 SACCHACHITIN 確實能夠抑制 B16 細胞中酪胺酸 ? 蛋白質的表現，尤其是當 SACCHACHITIN 濃度為 2 m g/ml 時，效果更加顯著，同時且隨著 SACCHACHITIN 的微粒化，有 增進抑制 B16 細胞中酪胺酸 ? 蛋白質表現的結果。
靈芝子實體細胞壁組成 SACCHACHITIN 對 B16 細胞黑色素形成抑制之探討
SACCHACHITIN was prepared from the waste residue of the fruiting body of Ganode rma taugae, was used in our previous study to inhibit matrix metalloproteinases and lipa se. In the present study, SACCHACHITIN was estimated for its effects on the tyrosinas e activity and expression. In the mushroom tyrosinase inhibition assay, the results indic ated that 2.5 mg/ml of ascorbic acid had strong inhibition of mushroom tyrosinase. In di fferent source of chitin, only SACCHACHITIN showed a potent tyrosinase activity inhi bition, IC50 value was 17.2 mg/ml. In the cell culture assay, SACCHACHITIN showed neither morphological alteration nor disorder in proliferation. These evidences elucidate d that SACCHACHITIN was not cytotoxic and safe toward the growth of B16 mouse m elanoma cells. Use 25nM -MSH induce melanogenesis in B-16 cells could elevate 3.3 7 times of melanin content. The results of inhibitory effect of SACCHACHITIN with n o inducer and with inducer -MSH on melanin biosynthesis and tyrosinase activity wer e observed in B-16 mouse melanoma cells all in a dose-dependent response reaction.
Western blot was employed to ensure SACCHACHITIN inhibited B16 cells tyrosinase protein expression, and the results indicated that 2.0 mg/ml SACCHACHITIN had obvi ously inhibitary effect. In the same experiment, SACCHACHITIN in small particle ( av erage size: 10 μm ) seemed in clined to enhance the inhibition of tyrosinase protein expr ession.
Inhibition of Melanogenesis in B16 cells by
SACCHACHITIN, a Cell Wall Component from Ganoderma tsugae
